AP and TS EAMCET Engineering Model Paper 3

In a test an examinee cither guesses or copies or knows the answer to a multiple choice question with four choices. The probability that he makes guess is

1

3

and the probability that he copies the answer is

1

6

. The probability that his answer is correct, given that he copied it is

1

8

. Then the probability that he knew the answer to the question, given that he correctly answered it is